Intravascular (IV) access is a mainstay of medical care, and provides a conduit for delivery of life-saving medications, fluids, and nutrition. Furthermore, venous access allows the aspiration and sampling of blood for diagnostic purposes to learn more about the medical patient. IV access may be within a peripheral vein, a central vein, or an intermediate placement such as a peripherally inserted central catheter (PICC) or midline/extended dwell peripheral IV (EDPIV). Intra-arterial access is also commonplace, and the archetype of arterial access is that of the well-described arterial “art” line. Rather than serving as a conduit for the administration of fluids as is seen in venous lines, arterial lines are most frequently employed for diagnostic purposes in the invasive, yet accurate, collection of vital signs and blood gases. Finally, arterial access also enables percutaneous introduction of vascular devices, namely hemostatic sheaths, for the subsequent introduction and exchange of various catheters, wires, and other endovascular devices.
Barriers to effective and safe intravascular access include limitations in patient anatomy, patient medical condition, potential loss of sterility, and user proficiency. Anatomic barriers include size and depth of the vessel, tortuosity or lack of a sufficient inline segment, vessel webs, vessel spasm, and lack of good direct or ultrasound visualization. When patients require intravascular access, they are often in an unhealthy state, which may further complicate the creation of durable access, including smaller vessels in the setting of dehydration or systemic illness, as well as concern for potential bleeding complications in the ill and anticoagulated patient. Additionally, pathologic conditions of the blood vessels exist, which may complicate vessel access. Venous varicosities, and both arterial and venous stenosis and vasospasm, are examples. Finally, sterility may be broken dependent on the preparation and positioning of the patient's access site, but may often be related to operator error while trying to control an unwieldy object, or make multiple device exchanges. All the aforementioned barriers may be further complicated by individual skill and training. Therefore, desirable attributes of a vascular access device include an intuitive device whose components, namely the wire, are user-friendly and sufficiently long enough to extend sufficiently within the vessel to maximize trackability, and ultimately, the technical success, sterility, and safety of introducing an integrated catheter.